Using Fibre Channel (FC) or iSCSI storage

The design of Swarm allows for a variety of choice when it comes to the disk storage that each node uses and this includes the use of Fibre Channel or iSCSI SANs. FC storage is always accessed through host bus adapter (HBA) cards while iSCSI has the option of using an HBA which is supported by Swarm or a fat driver stack on a standard Ethernet NIC which is not supported by Swarm. Standard HBA hardware offerings from Emulex and QLogic are supported in the Linux kernel that runs on Swarm nodes.

Use the following steps to use FC or iSCSI storage with Swarm.

Provision the LUNs for the Swarm node's HBA (storage array and switch fabric)
Configure the HBA in the Swarm node's BIOS if necessary
Use "vols = all" in the Swarm node's node.cfg file
Boot the node.

Verify that the LUNs show up as attached disk devices on the Swarm administration console. Depending on the HBA, the device names for the attached LUNs may or may not be the standard "/dev/sda", "/dev/sdb" style of names. The important thing to look for is the existence and size of the disk devices that show in the console.